Telephone-exchange apparatus



(No Model.)

W. M. GOODRIDGE.

TELEPHONE EXCHANGE APPARATUS. No. 367,754. Patented Aug. 2, 1887.

UNITED STATES PATENT OFFICE.

\VILLIAM M. GOODRIDGE, OF HIGHLAND PARK, ASSIGNOR TO THE \VESTERN ELECTRIC COMPANY, OF CHICAGO, ILLINOIS.

TELEPHONE-EXCHANGE APPARATUS.

SPECIPICATIDN forming part of Letters Patent No. 367,754, dated August 2, 1887.

Application filed Mart-h 4, 1887. Serial No. 229,668. (No model.)

To all whom, it may concern;

Be it known that I, WILLIAM M. Goon RIDGE, a citizen of the United States, residing at Highland Park, in the county of Lake and 5 State of 1llinois, have invented a certain new and useful Improvement in Telephone -EX- change Apparatus, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to telephone-exchange systems in which the different telephone-lines are each provided with a flexible cord and plug, so that any two lines may be connected together by simply inserting the plug of any line in a spring-jack or terminal connection of another line.

My invention relates more particularly to telephoneexchange apparatus in which multiple switch-boards are employed.

My invention will be readily understood by reference to the accompanying drawings, in whichv Figure 1 is a diagram illustrative of my invention, showing two telephone lines connected with two sections of a multiple switchboard, and the circuits and apparatus at the different sections for receiving and making the calls and connecting and disconnecting the 0 lines. Fig. 2 is a sectional view of the loop pl no; for looping the telephone into circuit.

Line a is shown connected through its springjacks I) 0, one on each of the sections, and from the switch b on the last section to the answer- 5 "ing spring -jack (Z of the line, and thence through individual annunciator e to the frame of spring-jackf. Plug g normally is inserted in spring -jack f, thus forming connection, through the medium of the plug, between said frame and the spring, and hence normally the circuit of line a may be traced from said frame of spring-jack fthrough the metallic point of the plug 9, thus inserted, to the spring of said switch, and from said spring to ground.

One of the novel features of my invention herein consists in providing an extra springjack, f, in the circuit of the telephone-line in which the plug 9 is normally inserted to close the circuit ofthe line to ground. WVhen thus inserted, it will be seen that the flexible cord from the annunciator and ground at the said answering spring jack, as shown. Thus the operator, on seeing a sh utter fall, at once loops his telephone into the line. \Vhen the 6 loopplng is thus inserted, it will be seen that the test-key 0, operatcd'by the lever of the answering spring-jack, is closed, and thus the test-wire of the line is connected with ground, as shown, so that the line will test busy as soon as the loop-plug is inserted in the answering spring-jack. The operator, being thus in connection with the subscriber, finds out what connection is wanted, and he thereupon withdraws plug in. from the spring-jack Z and inserts said plug in the spring-jack of the subscriber called for, and the two subscribers are thus connected together, the circuit being completed from the frame of the answering springjack 1 to the flexible cord, and thence to the tip of the plug m, which, inserted in the springjack of the called subscriber, is closed to the spring on line terminal of said called subscribcr. The operator, by means of one of the calling-keys q, throws current to line, and then removes the loop-plug and is ready for the next call.

The loop-plug being-removed, the test-key 0 will be opened, but the test-wire 1) will remain connected to ground through switch Z. Thus at all times the busytest is maintained.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. The telephone-line, in combination with a different switch on each section of the multiple-board, an answering spring 'ack on one of the sections of the switch-board included with an annunciator in the line and an additional spring-jack in theline between the said annunciator and ground, and a flexible branch roo from said line and a terminal plug, said plug nal plug normally inserted in the extra springbeing normally inserted in said extra springjack of its line, said plug on being removed jack and serving to close the line to ground taking off the ground and on being inserted in while the flexible branch or cord is shunted, the switch of another line serving to connect substantially as described. the two lines together.

2. The combination, in a multiple switeh- In witness whereof I hereunto subscribe my board system of telephone-exchange, of telename, this 6th day of January, A. D. 1887.

phone-lines each provided with a separate ,7 i switch on each section of the board, and on ILLIAM GOODRIDGE' Vitnesses:

one of the sections in each line an answering spring-jack, an annuneiator and an extra \VM. M. GILLER, spring-jack, and a flexible cord with itsternii- GEORGE E. BARTON. 

